1. Field of the Invention
The invention relates to a solid-state imaging apparatus, in particular to a package-type solid-state imaging apparatus enclosing a solid-state imaging device chip in a package.
2. Description of the Related Art
Recently, as a solid-state imaging apparatus to be mounted in an electronic device module such as a camera module used in a video camera, a digital camera, a mobile-phone with a camera, etc., a package-type solid-state imaging apparatus is widely adopted.
FIG. 1 illustrates an example of a package-type solid-state imaging apparatus of related art. A package-type solid-state imaging apparatus 1 encloses in a package 4 a solid-state imaging device chip 3 having a light reception part 2. An opening part opposing the light reception part 2 of the package 4 is closed with an optically transparent member 5. The package 4 is made of plastic, ceramic, glass, etc., and the solid-state imaging device chip 3 is arranged in an internal open space in the package 4. An external connection terminal 6 is led out from the package 4, and an inner lead 7 of the external connection terminal 6 and an electrode pad (not shown) of the solid-state imaging device chip 3 are bonded by a metal wire 8 to be electrically connected with each other. An adhesive layer 9 is formed on the surface of an internal wall of the package 4 so that a minute foreign substance floating in the internal open space of the package 4 adheres to the adhesive layer 9. The adhesive layer 9 prevents the minute foreign substance in the open space of the package 4, such as floating dust, etc., from adhering to the light reception part 3 of the solid-state imaging device chip 3 to exert a bad influence to image display (see, for example, Japanese Unexamined Patent Application Publication No. 2003-37256). If a foreign substance such as dust, etc. adheres to the imaging surface of the solid-state imaging device chip 3, when an image imaged with the solid-state imaging apparatus 1 is displayed, the foreign substance appears as a black spot or smear, so that the solid-state imaging apparatus 1 becomes an inferior product.
FIG. 2 illustrates another example of a package-type solid-state imaging apparatus of related art, which is configured as a so-called imaging module. An imaging module 11 includes a substrate 12, on the surface of which wirings (not shown) are formed, and a solid-state imaging device chip 13 mounted on the substrate 12 together with a chip part 14 such as a capacitor, a resistor, etc. A holder 15 supporting a light reception lens 16 and an infrared cut filter 17 is joined to the substrate 12 such that the solid-state imaging device chip 13 and the chip part 14 are closely sealed. The holder 15 includes a casing part 15a and a cylindrical part 15b, and an attachment 18 supporting the light reception lens 16 is engaged with the cylindrical part 15b. The solid-state imaging device chip 13 is electrically connected with a wiring connection electrode part 19 on the substrate 12 by a metal wire (so-called bonding wire) 21.
A resin 23 is formed on an upper wall surface of the casing part 15a through a stream stopping frame 22, and a resin 25 is formed through a stream stopping frame 24 such that the chip part 14 on the substrate 12 is buried. The resin 23 and the resin 25 have the adherence property. In this imaging module 11, even if dust adheres to the internal surface of the casing part 15a, peeling off of the dust is prevented by the resin 23 and the resin 25, and thereby occurrence of failure due to dust is avoided (see Japanese Unexamined Patent Application Publication No. 2006-165964).
Such package-type solid imaging apparatuses configured to prevent occurrence of failure by causing a minute foreign substance such as dust, etc. to adhere to the adhesive layer are also described in Japanese Unexamined Patent Application Publications No. 11-74495 and No. 2005-278034.